8 OKGANISED FLUIDS. 



Mr. Lane thinks that the division of the capillaries, which 

 necessarily takes place in the opening of the duct, allows of 

 the admission into its contents of the blood discs, which are 

 there found. Such are the several ways in which it has been 

 suggested that the blood corpuscles find entrance into the 

 thoracic duct. 



Mr. Gulliver has noticed that the blood corpuscles con- 

 tained in the chyle are usually much smaller than those taken 

 from the heart of the same animal, and also, that not more 

 than one fourth of the entire number present their ordinary 

 disc-like figure, the remainder being irregularly indented on 

 the edges, or granulated. The first of these observations, 

 viz. that which refers to the smaller size of the blood cor- 

 puscles found in the chyle, might be explained by supposing 

 that those corpuscles were in progress of formation, and that 

 they had not as yet attained their full development ; the 

 other remark, as to the deformed and granulated character 

 of the corpuscles, might be reconciled with the former expla- 

 nation, by supposing that some time had elapsed between 

 the death of the animal and the examination of the fluid of 

 the thoracic duct. If this manner of accounting for the 

 condition presented by the blood corpuscles of the chyle 

 should be proved to be insufficient, which I myself scarcely 

 think it will, then the only other mode of explaining their 

 appearances is by supposing that their presence in the chyle 

 is really foreign, and that, soon after their entrance into that 

 fluid, the blood corpuscles begin to pass through those changes, 

 indicative of commencing decomposition, of which they are 

 so readily susceptible. 



Leaving, however, for the present the question of the 

 origin of the red corpuscles of the blood, which will have to 

 be more fully discussed hereafter, we will in the next place 

 bestow a few reflections upon the origin of the white cor- 

 puscles : into this subject, however, it is not intended to 

 enter at any length at present, but merely to make such ob- 

 servations as seem more appropriately to find their place in 

 the chapter on the Chyle and Lymph. 



It has been noticed that the white corpuscles occur in 



